It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.
Digitized version of the Geologic Atlas of the United States, a set of 227 folios published by the U.S. Geological Survey between 1894 and 1945. Each folio includes both topographic and geologic maps for each quad represented in that folio, as well as description of the basic and economic geology of the area. Maintained by the Texas A & M University Libraries.
Devoted to geology and geology-related topics; includes a large collection of political and thematic maps for the United States and over 100 countries.